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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Aective Computing Experiments in Virtual Reality with Wearable Sensors. Methodological considerations and preliminary results.</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Grzegorz J. Nalepa</string-name>
          <email>grzegorz.j.nalepa@uj.edu.pl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jan Argasi«ski</string-name>
          <email>jan.argasinski@uj.edu.pl</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Krzysztof Kutt</string-name>
          <email>kkutt@agh.edu.pl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pawe“ Wƒgrzyn</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Szymon Bobek</string-name>
          <email>sbobek@agh.edu.pl</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mateusz Z. ƒpicki</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>AGH University of Science and Technology Al. Mickiewicza 30</institution>
          ,
          <addr-line>30-059 Krakow</addr-line>
          ,
          <country country="PL">Poland</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Jagiellonian University Ul. Go“ƒbia 24</institution>
          ,
          <addr-line>31-007 Krakow</addr-line>
          ,
          <country country="PL">Poland</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>3 See http://affect.media.mit.edu/projectpages/iCalm/iCalm-2-Q.html</p>
      </abstract>
      <kwd-group>
        <kwd>aective computing</kwd>
        <kwd>virtual reality</kwd>
        <kwd>aect metrics</kwd>
        <kwd>mobile devices</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        Aective computing (AfC) is a novel paradigm originally proposed in 1997 by
Rosalind Picard from MIT Media Lab in her paramount book [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]. It builds on
the results of biomedical engineering and psychology and aims at allowing
computer systems to detect, use, and express emotions [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. While at rst sight it may
look general from the computer science point of view, in fact it is a
constructive and practical approach oriented mainly at improving human-like decision
support as well as human-computer interaction. AfC is a eld of study that
puts interest in design and description of systems that are able to collect,
interpret, process (ultimately simulate) emotional states (aects). We assume that
emotions are physical and cognitive [12, p.21] and as such they can be studied
interdisciplinary by computer science, biomedical engineering and psychology.
For aective computing there are two crucial elements to be considered: modes
of data collection and ways of interpreting them in correlation with aective
states corresponding to emotions. First is carried out by selection of methods for
detecting information about emotions - this means using various sensors which
capture data about human physical states and behaviors. Today most often
harvested and processed information are about: speech (prosody: pitch variables,
speech rate), body gestures and poses (3D mapping, motion capture techniques),
facial expressions (visual analysis and electromyography), physiological
monitoring (blood pressure, blood volume pulse, galvanic skin response). In our work
we plan to use a range of wearable physiological sensors, namely the Empatica
E4. It is an advanced sensor based on the technologies previously developed in
the Aective Computing division of MIT Media Lab 3. Moreover, it was used
in some works [
        <xref ref-type="bibr" rid="ref10 ref13 ref16 ref17 ref5 ref6 ref9">5,6,9,10,13,16,17</xref>
        ]. Second crucial element of aective computing
paradigm relies on application of selected algorithms on acquired data to develop
models of interpretation for aective states. State of the art methodologies
assume the use of the full range of available methods of data classication and
interpretation.
      </p>
      <p>In this paper we discuss selected important challenges in designing
experiments that lead to data and information collection on aective states of
participants. We aim at acquiring data that would be basis to formulate and evaluate
computer methods for detection, identication interpretation of such aective
states, and ultimately human emotions.</p>
      <p>This work is result of cooperation between two research teams: one from
AGH UST led by Grzegorz J. Nalepa and second in Department of Games
Technology led by Pawe“ Wƒgrzyn. Early ideas were originally presented in the
project proposal entitled Knowledge-based models for aective context-aware
systems (KAFXS) written by Grzegorz J. Nalepa in cooperation with Jan K.
Argasi nski and Piotr Augustyniak. They were later developed and focused on the
development of practical experiments presented in this paper.
2</p>
      <p>Challenges in Designing Practical AfC Experiments
To design and conduct practical AfC experiments that could deliver valuable
aective data, a number of challenges has to be addressed.</p>
      <p>
        Dening emotion is a dicult problem. Without consensual
conceptualization and operationalization of exactly what phenomenon is to be studied,
progress in theory and research is hard to achieve and fruitless debates are likely
to proliferate. Modern theories of emotions have their origin in 19th century
William James theorized about aects in terms of reactions to stimuli. He was
precursor to appraisal theory which is among most popular in the community
of computational emotional modeling [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. One of the most popular
appraisal theories is OOC [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] which categorizes emotion on basis of appraisal
of pleasure/displeasure (valence) and intensity (arousal). These are quantiable
values that can be measured and processed ascribing dierent kinds of emotions.
      </p>
      <p>
        First of all, in our work we initially assume that emotions are results of
non-cognitive processes, as James proposed. More specically, we are aiming at
building on the somatic feedback theory of emotions form Jesse Prinz [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], which
is based on the James-Lange theory. It is assumed that embodied appraisals
manifest by the body and can be detected and measured. In fact Prinz proposes
a concept of core relational themes that could be possibly identied as patterns
in data using data mining.
      </p>
      <p>
        Therefore, we assume that we need to measure number of bodily signals to
detect and identify emotions. We begun our work with an in-depth analysis of
selected works in experimental psychology and biological psychology. A survey
paper [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] provided us with a pool of papers referring to the activity of Autonomic
nervous system (ANS) as with our methodological assumptions should be viewed
as a major component of the emotion response. The paper provides a review of
134 publications that report experimental investigations of emotional eects on
peripheral physiological responding in healthy individuals. The results suggests
important ANS response specicity in emotion when considering sub types of
distinct emotions. Moreover, some terminological assumptions are given.
      </p>
      <p>From our perspective, and considering our needs, the review turned out to
be mostly inconclusive and provided little support in designing our experiments.
Some of the main challenges are related to:
1. the use of discrete (e.g. Ekman’s faces) vs continuous (e.g. Russel’s
Circumex) models of emotions distinction between basic emotions vs high/social
emotions while naming emotions is a lot conceptualization and high level
semantics involved, that needs to be minimized the experimental assumptions
dier importantly, thus to comparison of results is questionable the
individual, and cultural dierences of participants need to be considered in some
cases how to evoke emotions in experimental setup, what are the optimal
stimuli which bodily signals should be used, how to measure and what to
measure (e.g. only HR and GSR values) what is the role of of user
questionnaires, in fact people need semantics (names of emotions) not numbers (e.g.
Valence/Arousal or HR value)</p>
      <p>There are also some other practical challenges that we will need to address
in the near future. They include (but are not limited to):
1. the quality of data from mobile devices, are the results from bands reliable
(is raw signal available?), there is an need for cross validation
2. volatile hardware market, devices change or get discontinued, (e.g. Microsoft</p>
      <p>Band 2)
3. reliable hardware and software setup,
4. data synchronization across several devices.</p>
      <p>
        Finally, an important challenge remains a synthetic way of reporting the
measure of emotion. There are number of approaches to do it. Some of them simply
assume reporting Valence/Arousal vales. We are dedicated to delivering more
synthetic methods that would combine data measurements with user reports.
Therefore, we are working on certain aective metrics that would include both
the measurements of bodily responses, as well as report and stimulus
evaluation by participants. Some other related works include the so-called Emotional
Index [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ].
3
      </p>
    </sec>
    <sec id="sec-2">
      <title>Methods and Tools Used</title>
      <p>The rst aim of cooperation of our two research groups is to provide:
1. an integrated sensoric framework which will use wearable physiological and
biomedical hardware sensors for detection of user aects,
2. computational models for aect identication and interpretation.</p>
      <p>To deliver solutions to the rst objective we need to use some small mobile
devices to acquire sensoric data. In our current experiments we selected 3 such
devices.</p>
      <p>
        Empatica E4. An advanced sensory wristband based on the technologies
previously developed in the Aective Computing division of MIT Media Lab 1.
Blood volume pulse and galvanic skin response sensors, as well as infrared
thermopile and accelerometer are on board. It has already been used in
number of works [
        <xref ref-type="bibr" rid="ref10 ref13 ref16 ref17 ref5 ref6 ref9">5,6,9,10,13,16,17</xref>
        ].
      </p>
      <p>Microsoft Band 2. Band developed mainly for tracking tness goals. Equipped
with optical heart rate and skin temperature sensors, accelerometer and
galvanic skin response (GSR) sensor available through well documented
Software Development Kit (SDK).
e-Health Sensor Platform. An open medical monitoring platform supervised
by the Cooking Hacks. It is a shield for Arduino/Raspberry Pi and the set
of sensors that can be plugged in: pulse, oxygen in blood (SPO2), airow
(breathing), body temperature, electrocardiogram (ECG), glucometer,
galvanic skin response (GSR), blood pressure (sphygmomanometer), patient
position (accelerometer) and muscle/electromyography sensor (EMG). Thanks
to build on Arduino, this solution can be combined with various devices and
installations.</p>
      <p>We are using dierent data acquisition methods for these three devices.
Basically, for E4 we use mobile applications delivered by Empatica (however, on a
desktop system), for Microsoft Band 22 we developed our own mobile app, and
for e-Health we use a basic setup for serial port data acquisition.</p>
      <p>Furthermore, sensor recordings are compiled with user surveys (see Figure 1)
prepared to determine which emotions were experienced during each stage of a
prepared experiment. In fact in our initial phase of research we prepared and
conducted several in lab experiments to verify our assumptions. The studies
were conducted with the use of Virtual Reality (VR) via Oculus headset to
provide emotional stimuli for more immersive user experience. Three experiments
were conducted to collect the data for preliminary analysis as well as for the
comparison of the signals collected by dierent devices.</p>
      <p>How do you feel during watching a movie?
unpleasantly
boredom
neutral
neutral
Fig. 1. Survey presented for each stage of the experiment (English adaptation for the
paper; during experiments Polish version was used). In addition, the participant was
able to describe the emotions in his own words below.
pleasantly
fascination</p>
      <p>What do you feel?</p>
      <p>Sadness Joy Rage</p>
      <p>Anxiety Surprise Fear
Irritation Shame Contempt</p>
      <p>Guilt Disgust Pleasure</p>
      <p>Desperation Pride
NONE OF THE ABOVE</p>
    </sec>
    <sec id="sec-3">
      <title>Preliminary Experiments</title>
      <p>All of the experiments were prepared and conducted by the Authors in the
Department of Games Technology at Jagiellonian University in July, September,
and October 2016.</p>
      <p>Experiment 1: Secondary School students. First experiment was conducted in
July as a part of a holiday camp for secondary school students. 7 pupils (men)
was connected to three devices (Empatica E4, Microsoft Band 2, e-Health Sensor
Platform) during the test procedure. Signals measured by all devices: Heart Rate
(HR), Galvanic Skin Response (GSR), Skin Temperature.</p>
      <p>Experiment consists of 4 stages that took place in Virtual Reality (VR)
environment: (a) introductory movie without interaction, (b) three tasks with
architecture tool (changing colors or moving furniture around), (c) jump scare,
(d) movie without interaction to calm down participants.</p>
      <p>Experiment 2: The Scientist’s Night. Second study was conducted during the
Scientist’s Night at Jagiellonian University in September. More than 100
participants take part in between-subject procedure: each participant was connected
only to one of three devices (Empatica E4, Microsoft Band 2, e-Health Sensor
Platform) during the experiment. This plan was adopted due to the nature of
the event: a lot of people and chaos do not give a possibility to conduct
withinsubject study as before. Signals measured by all devices: HR, GSR.</p>
      <p>During experiment, 6 participants were at the scene: three was watching
movie in VR and another three was dealing with papers (agreement to participate
in the study before movie, survey after movie). In order to simplify and shorten
the procedure, only one movie, approx. 5 minutes long, was presented.
Experiment 3: The Scientist’s Night follow-up study. The third study was
performed with the same procedure using the same tools as during Scientist’s
Night, but to make it very calmly, slowly and accurately. The planned group is
30 persons (10 persons x 3 devices).</p>
      <p>The data from these experiments is currently being analyzed. The results
will be presented during the workshop.
5</p>
    </sec>
    <sec id="sec-4">
      <title>Future Works</title>
      <p>During the AfCAI workshop in Murcia we presented in more details the
experiments and shared the experiences we got.</p>
      <p>Our next steps for future works include cross validation and evaluation of
mobile bands data, evaluation restriction to HR, GSR signals, provisioning several
conguration of emotion evoking setup, combination of VR experiments with
odor stimuli, delivery of several veried data sets for further analysis, and nally
position and constraint research with specic applications and projects.</p>
      <p>
        Furthermore, we aim at developing data acquisition layer integrated with
our recent solutions [
        <xref ref-type="bibr" rid="ref2 ref3">2,3</xref>
        ] in the area of mobile context-aware systems. We
proposed methods for improving of knowledge management methods for imperfect
or incomplete context that allow for modeling dynamics of the uncertainty and
provide ecient reasoning under incomplete or missing data; as well as new
modeling and context processing methods that improves the system capabilities
to self-adaptability in dynamic mobile environments. The rapidly changing and
uncertain nature of the physiological context, and the need to explain to the user
the system behavior makes the deliverables of our previous research t perfectly
the AfCAI motivations.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>The authors would like to thank the participants of the Cognitive Science
Seminar for Philosophy PhD Students in spring 2016. Moreover, special thanks go to
Dr Micha“ Klincewicz for his remarks on methods in experimental psychology.
Finally, we would like to thank our students who helped us with the experiments,
and data treatment, especially the AfC group in the KECS course in 2016.</p>
    </sec>
  </body>
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